Truncated dome cup

ABSTRACT

A formed blank is provided. The formed blank includes a stretched portion and/or a truncated protrusion, a tooling assembly structured to form a formed blank including a stretched portion and/or a truncated protrusion, and a method of forming a formed blank including a stretched portion and/or a truncated protrusion. The formed blank includes a base and a depending sidewall. The stretched portion and/or the truncated protrusion is disposed on the formed blank base and the thickness of the stretched portion and/or the truncated protrusion is less than the sidewall. The stretched portion and/or the truncated protrusion utilizes less material relative to an unformed base that has about the same thickness as the sidewall.

BACKGROUND OF THE INVENTION Field of the Invention

The disclosed concept relates generally to containers and, moreparticularly, to metal containers such as, for example, beer or beveragecans, as well as food cans. The disclosed concept also relates to cupsand blanks for forming cups and containers. The disclosed conceptfurther relates to methods and tooling for selectively forming a cup orbottom portion of a container to reduce the amount of material in thecup or bottom portion.

Background Information

It is generally well known to draw and iron a sheet metal blank to makea thin walled container or can body for packaging beverages (e.g.,carbonated beverages; non-carbonated beverages), food or othersubstances. As is known, many such containers have a generallycylindrical shape and the example discussed herein is assumed to havesuch a shape. It is understood, however, that the disclosed container(as well as the cup that becomes the container) method for forming sucha container/cup is not limited to this specific shape.

One of the initial steps in forming such containers is to form a cup. Asshown in FIG. 1, the cup begins as a generally planar blank I cut fromsheet material. The blank 1 is then drawn into a cup 2. The cup 2 isgenerally shorter and wider than the finished container. Accordingly,the cups 2 are typically subjected to a variety of additional processesthat further form the cup into the finished container. The cup includesa base 3 having an upwardly depending sidewall 4. The container body,hereinafter can body 5 (FIG. 2), is formed by additional processes suchas, but not limited to, drawing, redrawing, and ironing the cup 1. Thecan body 5 also includes a base 6 and a sidewall 7. The can body base 6includes a bottom profile. That is, as used herein, a “bottom profile”is the shape of the base 3, 6 after forming. Generally, a beverage canbody 5A, the bottom profile slopes inwardly from an annular ridge 8 toform an inwardly projecting, generally hemispherical dome 9. Conversely,a food can body 5B (shown during formation in FIG. 4E) has a generallyflat bottom profile. The dome 9 is formed by a “domer” during theforming of the cup 2 and/or a can body 5. The apparatus and toolingstructured to form a cup 2 and/or a can body 5 is shown in U.S. patentapplication Ser. No. 15/286,954, which is incorporated by reference.

There is a constant desire in the industry to reduce the gauge, and thusthe amount of material used to form such containers. However, amongother disadvantages associated with the formation of containers fromrelatively thin gauge material, is the tendency of the container towrinkle, particularly during redrawing and doming. Prior proposals have,in large part, focused on forming bottom profiles of various shapes thatwere intended to be strong and, therefore, capable of resisting bucklingwhile enabling metal having a thinner base gauge to be used to make thecan body. As used herein, “base gauge” means the initial thickness ofthe material and is not limited to the thickness of the baseportion/element. Thus, the conventional desire has been to maintain thematerial thickness in the dome and bottom profile to maintain orincrease strength in this area of the can body and thereby avoidwrinkling.

Tooling for forming domed cups or can bodies has conventionally includeda curved, or arcuate, punch core and a die core with a correspondingcurvature, such that a domed can body is formed from material (e.g.,without limitation, a sheet metal blank) conveyed between the punch coreand the die core. Typically, the punch core extends downwardly into thedie core, forming the domed cup or can body. During this formingoperation, the material is drawn between the punch core and the diecore. That is, in order to maintain the thickness of the domed portion,the material is relatively lightly clamped on either side of the portionto be domed. Thus, the material can move (e.g., slide) or flow towardthe dome as it is formed in order to maintain the desired thickness inthe bottom profile. Further, as shown in U.S. Pat. No. 5,394,727, it isknown to form a bottom profile including generally planar (when viewedin cross-section) surfaces instead of a dome. Such protrusions are alsoformed by drawing the material over a die. The domes and protrusions ofthe known art are structured to generally maintain the thickness of thematerial during the formation of a dome.

Further, can bodies formed from a cup with a generally hemisphericaldome also have disadvantages. For example, certain beverage can bodiesare formed by reversing, or flattening, the dome on the cup andreforming the dome on the can body. The steps to this process are shownin FIGS. 3A-3C and include reversing the dome (FIGS. 3B and 3C) andreforming a can body dome (FIGS. 3D and 3E). It is noted that a cup'sgenerally arcuate dome, i.e., a generally hemispherical dome isgenerally arcuate in cross-section as shown in the figures, defines avolume of metal. This volume of metal must be reformed when the cup isformed into a can body. Further, it is noted that a generally arcuatedome includes a greater volume of metal relative to other shapes suchas, but not limited to a truncated dome, as shown in FIG. 5A, discussedbelow. This greater volume of metal allows the metal to wrinkle or haveother defects during the formation of the can body. This is also truefor food can bodies, which typically have a generally planar bottom,when formed from a cup with a generally arcuate dome. That is, the stepsof forming a food can body are shown in FIGS. 4A-4E. As with beveragecan bodies, the greater volume of metal in a generally hemisphericaldome, i.e., a generally arcuate dome when viewed in cross-section,allows for the formation of defects in the food can body when the cup isreformed.

There is, therefore, room for improvement in containers such asbeer/beverage cans and food cans, as well as in selectively formed cupsand tooling and methods for providing such cups and containers. That is,the problem in the known art is that the cup, or can body, uses too muchmaterial, especially in the base.

SUMMARY OF THE INVENTION

The disclosed and claimed concept provides for a formed blank includinga stretched portion and/or a truncated protrusion, a tooling assemblystructured to form a formed blank including a stretched portion and/or atruncated protrusion, and a method of forming a formed blank including astretched portion and/or a truncated protrusion. The formed blankincludes a base and a depending sidewall. The stretched portion and/orthe truncated protrusion is disposed on the formed blank base and thethickness of the stretched portion and/or the truncated protrusion isless than the sidewall. The stretched portion and/or the truncatedprotrusion utilizes less material relative to an unformed base that hasabout the same thickness as the sidewall. As such, the formed blank, thetooling for forming the formed blank, and the method of forming theformed blank solve the problems stated above.

BRIEF DESCRIPTION OF THE DRAWINGS

A full understanding of the invention can be gained from the followingdescription of the preferred embodiments when read in conjunction withthe accompanying drawings in which:

FIG. 1 is a cross-sectional view of a prior art cup.

FIG. 2 is a cross-sectional view of a prior art can body.

FIGS. 3A-3E show the formation of a prior art beverage can body.

FIGS. 4A-4E show the formation of a prior art food can body.

FIG. 5A is a cross-sectional view of a formed blank in the form of acup. FIG. 5B is a cross-sectional view of a formed blank in the form ofa can body.

FIG. 6 is a partially schematic, cross-sectional view of a toolingassembly.

FIG. 7 is a detail cross-sectional view of a domer structured to form atruncated protrusion.

FIGS. 8A-8E show the formation of a beverage can body from a cup with atruncated dome.

FIGS. 9A-9E show the formation of a food can body from a cup with atruncated dome.

FIG. 10 is a flow chart for the disclosed method.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Directional phrases used herein, such as, for example, clockwise,counterclockwise, left, right, top, bottom, upwards, downwards andderivatives thereof, relate to the orientation of the elements shown inthe drawings and are not limiting upon the claims unless expresslyrecited therein.

As used herein, the singular form of “a,” “an,” and “the” include pluralreferences unless the context clearly dictates otherwise.

As used herein, “structured to [verb]” means that the identified elementor assembly has a structure that is shaped, sized, disposed, coupledand/or configured to perform the identified verb. For example, a memberthat is “structured to move” is movably coupled to another element andincludes elements that cause the member to move or the member isotherwise configured to move in response to other elements orassemblies. As such, as used herein, “structured to [verb]” recitesstructure and not function. Further, as used herein, “structured to[verb]” means that the identified element or assembly is intended to,and is designed to, perform the identified verb. Thus, an element thatis merely capable of performing the identified verb but which is notintended to, and is not designed to, perform the identified verb is not“structured to [verb].”

As used herein, “associated” means that the elements are part of thesame assembly and/or operate together, or, act upon/with each other insome manner. For example, an automobile has four tires and four hubcaps. While all the elements are coupled as part of the automobile, itis understood that each hubcap is “associated” with a specific tire.

As used herein, the statement that two or more parts or components are“coupled” shall mean that the parts are joined or operate togethereither directly or indirectly, i.e., through one or more intermediateparts or components, so long as a link occurs. As used herein, “directlycoupled” means that two elements are directly in contact with eachother. As used herein, “fixedly coupled” or “fixed” means that twocomponents are coupled so as to move as one while maintaining a constantorientation relative to each other. Accordingly, when two elements arecoupled, all portions of those elements are coupled. A description,however, of a specific portion of a first element being coupled to asecond element, e.g., an axle first end being coupled to a first wheel,means that the specific portion of the first element is disposed closerto the second element than the other portions thereof. Further, anobject resting on another object held in place only by gravity is not“coupled” to the lower object unless the upper object is otherwisemaintained substantially in place. That is, for example, a book on atable is not coupled thereto, but a book glued to a table is coupledthereto.

As used herein, a “fastener” is a separate component structured tocouple two or more elements. Thus, for example, a bolt is a “fastener”but a tongue-and-groove coupling is not a “fastener.” That is, thetongue-and-groove elements are part of the elements being coupled andare not a separate component.

As used herein, the phrase “removably coupled” or “temporarily coupled”means that one component is coupled with another component in anessentially temporary manner. That is, the two components are coupled insuch a way that the joining or separation of the components is easy andwould not damage the components. For example, two components secured toeach other with a limited number of readily accessible fasteners, i.e.,fasteners that are not difficult to access, are “removably coupled”whereas two components that are welded together or joined by difficultto access fasteners are not “removably coupled.” A “difficult to accessfastener” is one that requires the removal of one or more othercomponents prior to accessing the fastener wherein the “other component”is not an access device such as, but not limited to, a door.

As used herein, “temporarily disposed” means that a first element(s) orassembly (ies) is resting on a second element(s) or assembly(ies) in amanner that allows the first element/assembly to be moved without havingto decouple or otherwise manipulate the first element. For example, abook simply resting on a table, i.e., the book is not glued or fastenedto the table, is “temporarily disposed” on the table.

As used herein, “operatively coupled” means that a number of elements orassemblies, each of which is movable between a first position and asecond position, or a first configuration and a second configuration,are coupled so that as the first element moves from oneposition/configuration to the other, the second element moves betweenpositions/configurations as well. It is noted that a first element maybe “operatively coupled” to another without the opposite being true.

As used herein, a “coupling assembly” includes two or more couplings orcoupling components. The components of a coupling or coupling assemblyare generally not part of the same element or other component. As such,the components of a “coupling assembly” may not be described at the sametime in the following description.

As used herein, a “coupling” or “coupling component(s)” is one or morecomponent(s) of a coupling assembly. That is, a coupling assemblyincludes at least two components that are structured to be coupledtogether. It is understood that the components of a coupling assemblyare compatible with each other. For example, in a coupling assembly, ifone coupling component is a snap socket, the other coupling component isa snap plug, or, if one coupling component is a bolt, then the othercoupling component is a nut.

As used herein, “correspond” indicates that two structural componentsare sized and shaped to be similar to each other and may be coupled witha minimum amount of friction. Thus, an opening which “corresponds” to amember is sized slightly larger than the member so that the member maypass through the opening with a minimum amount of friction. Thisdefinition is modified if the two components are to fit “snugly”together. In that situation, the difference between the size of thecomponents is even smaller whereby the amount of friction increases. Ifthe element defining the opening and/or the component inserted into theopening are made from a deformable or compressible material, the openingmay even be slightly smaller than the component being inserted into theopening. With regard to surfaces, shapes, and lines, two, or more,“corresponding” surfaces, shapes, or lines have generally the same size,shape, and contours.

As used herein, a “planar body” or “planar member” is a generally thinelement including opposed, wide, generally parallel surfaces, i.e., theplanar surfaces of the planar member, as well as a thinner edge surfaceextending between the wide parallel surfaces. That is, as used herein,it is inherent that a “planar” element has two opposed planar surfaces.The perimeter, and therefore the edge surface, may include generallystraight portions, e.g., as on a rectangular planar member, or becurved, as on a disk, or have any other shape.

As used herein, a “path of travel” or “path,” when used in associationwith an element that moves, includes the space an element moves throughwhen in motion. As such, any element that moves inherently has a “pathof travel” or “path.”

As used herein, the statement that two or more parts or components“engage” one another shall mean that the elements exert a force or biasagainst one another either directly or through one or more intermediateelements or components. Further, as used herein with regard to movingparts, a moving part may “engage” another element during the motion fromone position to another and/or may “engage” another element once in thedescribed position. Thus, it is understood that the statements, “whenelement A moves to element A first position, element A engages elementB,” and “when element A is in element A first position, element Aengages element B” are equivalent statements and mean that element Aeither engages element B while moving to element A first position and/orelement A either engages element B while in element A first position.

As used herein, “operatively engage” means “engage and move.” That is,“operatively engage” when used in relation to a first component that isstructured to move a movable or rotatable second component means thatthe first component applies a force sufficient to cause the secondcomponent to move. For example, a screwdriver may be placed into contactwith a screw. When no force is applied to the screwdriver, thescrewdriver is merely “coupled” to the screw. If an axial force isapplied to the screwdriver, the screwdriver is pressed against the screwand “engages” the screw. However, when a rotational force is applied tothe screwdriver, the screwdriver “operatively engages” the screw andcauses the screw to rotate. Further, with electronic components,“operatively engage” means that one component controls another componentby a control signal or current.

As used herein, the word “unitary” means a component that is created asa single piece or unit. That is, a component that includes pieces thatare created separately and then coupled together as a unit is not a“unitary” component or body.

As used herein, the term “number” shall mean one or an integer greaterthan one (i.e., a plurality).

As used herein, in the phrase “[x] moves between its first position andsecond position,” or, “[y] is structured to move [x] between its firstposition and second position,” “[x]” is the name of an element orassembly. Further, when [x] is an element or assembly that moves betweena number of positions, the pronoun “its” means “[x],” i.e., the namedelement or assembly that precedes the pronoun “its.”

As used herein, “about” in a phrase such as “disposed about [an element,point or axis]” or “extend about [an element, point or axis]” or “[X]degrees about an [an element, point or axis],” means encircle, extendaround, or measured around. When used in reference to a measurement orin a similar manner, “about” means “approximately,” i.e., in anapproximate range relevant to the measurement as would be understood byone of ordinary skill in the art.

As used herein, a “radial side/surface” for a circular or cylindricalbody is a side/surface that extends about, or encircles, the centerthereof or a height line passing through the center thereof As usedherein, an “axial side/surface” for a circular or cylindrical body is aside that extends in a plane extending generally perpendicular to aheight line passing through the center. That is, generally, for acylindrical soup can, the “radial side/surface” is the generallycircular sidewall and the “axial side(s)/surface(s)” are the top andbottom of the soup can.

As employed herein, the terms “can” and “container” are usedsubstantially interchangeably to refer to any known or suitablecontainer, which is structured to contain a substance (e.g., withoutlimitation, liquid; food; any other suitable substance), and expresslyincludes, but is not limited to, beverage cans, such as beer and sodacans, as well as food cans.

As used herein, a “contour” means the line or surface, that defines anobject. That is, for example, when viewed in cross-section, the surfaceof a three-dimensional object is reduced to two dimensions; thus, aportion of a three-dimensional surface contour is represented by atwo-dimensional line contour.

As used herein, a “perimeter portion” means the area at the outer edgeof a defined area, surface, or contour.

As used herein, a “truncated protrusion” is a profile for a cup base ora can body base that includes a “stretched portion” and a generallyplanar portion at the distal end of the protrusion, i.e., the end of theprotrusion located furthest from the base. Thus, as used herein, a“truncated protrusion” inherently includes a stretched portion and agenerally planar portion. Further, as used herein, a “generally planarportion” of a “truncated protrusion” includes both substantially planarelements and elements that include beads, corrugations, or similarconstructs structured to accommodate additional material in a definedarea and relative to a substantially planar element having the samedefined area so long as the area including beads, corrugations, orsimilar constructs has generally planar contour over the defined area.Further, as used herein, a “truncated protrusion” is formed and offsetinwardly. That is, a “truncated protrusion” is formed by deformingmaterial into the space partially enclosed by a base and sidewall, suchas on a cup of can body. Thus, the formation of an outwardly protrudingbead extending about base does not convert the generally planar portionof the base encircled by the bead into a “truncated protrusion” becausethe generally planar portion of the base encircled by the bead is notformed or offset inwardly.

As used herein, a “truncated protrusion forming profile” is a surface ona forming element, such as, but not limited to, the surface of a die,structured to form a material into a “truncated protrusion” as definedabove. As used herein, a “die truncated protrusion forming profile” is asurface on a die, structured to form a material into a “truncatedprotrusion” as defined above.

As used herein, a “truncated dome” is a “truncated protrusion” having agenerally curvilinear (or arcuate) portion and a generally planarportion when viewed in a lateral cross-section; that is, a truncateddome is a dome wherein a generally planar portion is disposed where thevertex of the dome would be, i.e., a dome with a generally flat top.Further, the “stretched portion” and the “generally planar portion” areone configuration selected from the group consisting of coextensive(i.e., fully overlapping), partially coextensive (i.e., partiallyoverlapping), or separate (i.e., no overlap).

As used herein, a “truncated dome forming profile” is a surface on aforming element, such as, but not limited to, the surface of a die,structured to form a material into a “truncated dome” as defined above.As used herein, a “die truncated dome forming profile” is a surface on adie, structured to form a material into a “truncated dome” as definedabove.

As used herein a “stretched portion” is a portion of a material formedby stretching the material. Further, as used herein, a “stretchedportion” is not an unstretched portion that is capable of beingstretched but rather one that has been stretched. Thus, an unstretchedportion that is capable of being stretched is specifically excluded fromthe definition of a “stretched portion.” A “truncated protrusion” or a“truncated dome,” in an exemplary embodiment, includes an unstretchedportion as well as the required “stretched portion.” That is, aprotrusion/dome with only an unstretched portion, i.e., lacking a“stretched portion,” is specifically excluded from the definition of a“truncated protrusion” or a “truncated dome.” Further, due to theabsence of a “stretched portion,” a protrusion formed exclusively bydrawing, such as the protrusion(s) disclosed in U.S. Pat. No. 5,394,727,are specifically excluded from the definition of a “truncatedprotrusion” and a “truncated dome.”

As used herein, a “formed blank” means a cup as well as a can body thathas been formed from a cup.

As used herein, “depending” means to extend at an angle other than zero(0°) from another element without regard to direction. That is, forexample, a “depending” sidewall may extend generally upwardly from abase.

As used herein, “generally curvilinear” includes elements havingmultiple curved portions, combinations of curved portions and planarportions, and a plurality of planar portions or segments disposed atangles relative to each other thereby forming a curve.

As used herein, “generally” means “in a general manner” relevant to theterm being modified as would be understood by one of ordinary skill inthe art.

As used herein, “substantially” means “for the most part” relevant tothe term being modified as would be understood by one of ordinary skillin the art.

As used herein, “at” means on and near relevant to the term beingmodified as would be understood by one of ordinary skill in the art.

Generally, and as shown in FIGS. 5A and 5B, a formed blank 10, i.e., acup 2 or a can body 5, is formed from a blank 1. That is, blank 1 isformed by a tooling assembly 100, shown partially schematically in FIG.6. As is known, the tooling assembly 100 includes a first tool assembly102 and a second tool assembly 104. At least one of the first toolassembly 102 and the second tool assembly 104 is movable and is coupledto a press 106 or similar device. In an exemplary embodiment, the firsttool assembly 102 includes a forming punch 108 and the second toolassembly 104 includes a forming die 110. The press 106 is structured to,and does, move the first tool assembly 102 between a first position,wherein the first tool assembly 102 is spaced from the second toolassembly 104, and a second position, wherein the first tool assembly 102is immediately adjacent and minimally spaced from the second toolassembly 104. That is, as the first tool assembly 102 moves from thefirst position to the second position, the forming punch 108 engages anddeforms blank 1 and forms the blank into a formed blank 10. As is known,the tooling assembly 100, in one embodiment, is supplied with pre-cutblanks 1 to be formed into cups 2. In another embodiment, the toolingassembly 100 is supplied with a sheet of material (not shown) and cutsblanks 1 from the sheet as part of the forming operation.

The following disclosure details the formation of a cup 2 which is thenformed into a can body 5, as is generally known. The cup 2, and thesubsequent can body 5, hereinafter and collectively the formed blank 10,includes a truncated protrusion 20, as shown in FIGS. 5A and 5B.Initially, however, the following disclosure details the configurationof the finished formed blank 10. That is, the formed blank 10 includes abody 11 having a base 12 and a depending sidewall 14. Further, as isknown, a can body base 12 includes a ridge 16 extending about the base12. In an exemplary embodiment, the base 12 is generally circular and,as such, the depending sidewall 14 is generally cylindrical and theridge 16 is an annular ridge 16′. Further, in an exemplary embodiment,the truncated protrusion 20 is a truncated dome 22. That is, the base 12includes a truncated protrusion 20 including a number of generallycurvilinear portion(s) 30 and a generally planar portion 32. It is notedthat the cup 2 shown in FIG. 5A has a single bead (not numbered) and isa cup 2 for a beverage can body 5A. Conversely, the cup shown in FIG. 9A(not numbered) has two beads and is for a food can body 5B. Generally, acup 2 for a food can body 5B has a greater diameter than a cup 2 for abeverage can body 5A and, as such, can accommodate another bead.

Further, compared to a generally hemispherical dome, i.e., a generallyarcuate dome when viewed in cross-section, a truncated dome 22 has a“reduced volume.” As used herein, a “reduced volume” means a protrusionformed in the bottom of a cup, such as, but not limited to, a truncateddome that has a reduced volume of metal compared to a generallyhemispherical dome, i.e., a generally arcuate dome when viewed incross-section. It is noted that the length of the bottom profile (whenviewed in cross-section as shown in FIG. 5A) of a truncated dome 22,i.e., the length from the outer edge of the truncated dome 22 to thecenter of the truncated dome 22 is shorter than the length of agenerally hemispherical dome because the generally planar portion 32 ofa truncated dome 22 has a shorter length relative to an arc on agenerally hemispherical dome. Stated alternately, when an arc within andconfined by a perimeter, e.g., sidewalls 14 (when viewed incross-section), is flattened to a generally straight line, the length ofthe now flattened line is shorter relative to the previously existingarc. Thus, as this distance is shorter, the volume of the truncated dome22 is less than a generally hemispherical dome having the same diameter.

In one exemplary embodiment, not shown, there is a single curvilinearportion 30 that extends between the annular ridge 16′ and the generallyplanar portion 32. Further, the single curvilinear portion 30 is, in anexemplary embodiment, an arcuate portion 40. As used herein, the term“arcuate portion” refers to the shape of the truncated protrusion 20when viewed in cross-section, as shown in FIG. 5A; it is understood thatthe curvilinear portion 30 (or arcuate portion 40) when rotated about anaxis in three dimensions forms a dome, or dome-like, shape. In theembodiment shown, the number of generally curvilinear portion(s) 30includes a first generally curvilinear portion 34 and a second generallycurvilinear portion 36. The truncated dome first generally curvilinearportion 34 has a first center, and, the truncated dome second generallycurvilinear portion 36 has a second center. As used herein, the “center”of a curvilinear line means a point that is disposed generally an equaldistance from all points on the curvilinear line; for an arcuate line,the “center” means a point that is disposed substantially an equaldistance from all points on the arcuate line. In an exemplaryembodiment, the first generally curvilinear portion 34 and the secondgenerally curvilinear portion 36 are a first generally arcuate portion44 and a second generally arcuate portion 46, respectively.

Further, as discussed in more detail below, a portion of the truncatedprotrusion 20 (or truncated dome 22) is stretched (hereinafter the“stretched portion” 38) during the forming process so that the materialforming the truncated protrusion 20, or a portion of the truncatedprotrusion 20, is thinner than the base gauge of the original material,i.e., the base gauge of the blank 1 which, in an exemplary embodiment,is also the thickness of the sidewall 14. In an exemplary embodiment,substantially all of the truncated protrusion 20 (or truncated dome 22)has a uniform thickness. That is, in one exemplary embodiment, thestretched portion 38 extends over substantially all of the curvilinearportion(s) 30 (34, 36) as well as the planar portion 32. In otherembodiments, the stretched portion 38 extends over only a portion of thecurvilinear portion(s) 30 (34, 36) and/or the planar portion 32.Further, in an exemplary embodiment, the truncated protrusion 20 (ortruncated dome 22) has a thickness that is between about 0.0003 inch and0.002 inch thinner than the base gauge of the original material and/orthe sidewall 14.

Generally, the tooling and method of forming a cup 2 or can body 5 witha stretched dome is disclosed in U.S. patent application Ser. No.15/286,954. The following disclosure addresses the details of thetooling assembly 100, shown in FIG. 6, and method (FIG. 10) for forminga truncated protrusion 20 (or truncated dome 22). As noted above, thetooling assembly 100 includes a first tool assembly 102 and a secondtool assembly 104 structured to form a blank 1 into formed blank 10,i.e. , a cup 2 or a can body 5. It is noted that the blank 1 has a basegauge (thickness) and that, after the initial formation of the formedblank 10, the base 12 and the sidewall 14 have substantially the samethickness as the base gauge. Further, in an exemplary embodiment, thetooling assembly 100 is structured to, and does, maintain the thicknessof the sidewall 14 substantially at the base gauge.

The first tool assembly 102 and second tool assembly 104 are furtherstructured to, and do, clamp the blank 1 of material at the periphery ofthe base 12. In an exemplary embodiment, the periphery of the base 12 isdefined by the ridge 16; thus, the first tool assembly 102 and secondtool assembly 104 are further structured to, and do, clamp the blank 1of material at the ridge 16. The first tool assembly 102 and the secondtool assembly 104 are structured to, and do, stretch a portion of thebase 12 and thereby thin the base stretched portion 38 relative to thebase gauge of the material and/or the sidewall 14. As discussed above,the stretched portion 38, in an exemplary embodiment, has a generallyuniform thickness. Further, in an exemplary embodiment, the stretchedportion 38 is coextensive with the entire base 12. To accomplish this,the formed blank 10 is moved by the forming punch 108 to the forming die110. The forming punch 108, in this embodiment, is an elongated,generally cylindrical body 112 with a cavity 114 at the distal end. Thecavity 114, in one embodiment, is generally concave and contoured tocorrespond to the shape of a forming surface 120, discussed below. Inanother embodiment, the cavity 114 is generally cylindrical; that is,the forming punch 108 is generally hollow.

As shown in FIG. 6, the forming surface 120 is disposed on the formingdie 110 of the second tool assembly 104. In an exemplary embodiment, theforming die 110 remains substantially stationary relative to the formingpunch 108. That is, the forming punch 108 reciprocates in a generallyvertical direction and the upper surface of the forming die 110 has aconvex protrusion 111 that defines the forming surface 120. The formingsurface 120 includes a truncated protrusion forming profile 122. Thus,the forming punch 108 is structured to, and does, move the blank 1 ofmaterial into contact with the truncated protrusion forming profile 122.In an exemplary embodiment, the truncated protrusion forming profile 122is a truncated dome forming profile 122′.

The truncated dome forming profile 122′ includes a number of generallycurvilinear portions 126 and a planar portion forming construct 128. Toform a truncated dome 22 as described above, the truncated dome formingprofile number of generally curvilinear portions 126 includes a firstgenerally curvilinear portion 130 and a second generally curvilinearportion 132. The truncated dome forming profile first generallycurvilinear portion 130 has a first center 134 and the truncated domeforming profile second generally curvilinear portion 132 has a secondcenter 136. Further, in an exemplary embodiment, the truncated domeforming profile first generally curvilinear portion 130 is a firstgenerally arcuate portion 140, and, the truncated dome forming profilesecond generally curvilinear portion 132 is a second generally arcuateportion 142.

The truncated dome forming profile planar portion forming construct 128is in one exemplary embodiment, not shown, a generally planar surface.That is, the truncated dome forming profile 122′ is generally flat atthe vertex. In the embodiment shown, the truncated dome forming profileplanar portion forming construct 128 is a cavity 150. That is, thetruncated dome forming profile 122′ is defined by the number ofgenerally curvilinear portions 126. The truncated dome forming profileplanar portion forming construct is the cavity 150 in the die. Statedalternately, the number of generally curvilinear portions 126 extendgenerally concentrically about a cavity 150.

In this configuration, the formed blank 10, and more specifically thebase 12, is clamped between the first tool assembly 102 and the secondtool assembly 104 as it is moved into the forming die 110. As theforming punch 108 moves the base 12 over the truncated dome formingprofile 122′, the material of the base 12 is stretched and thinned.Further, the material of the base 12 is formed to the contour of thetruncated dome forming profile 122′. That is, a portion of the base 12is formed to the truncated dome forming profile first generallycurvilinear portion 130 and the truncated dome forming profile secondgenerally curvilinear portion 132. Further, as the center of the formingdie 110 is hollow (and as the forming punch 108 is also hollow) thecenter of the base 12 remains generally planar while being thinned. Inan exemplary embodiment, the first tool assembly 102 and the second toolassembly 104 are structured to form the formed blank sidewall 14 with athickness about the same as the base gauge. The first tool assembly 102and the second tool assembly 104 are also structured to form the formedblank truncated protrusion with a thickness that is less than the formedblank sidewall 14. In an exemplary embodiment, the first tool assembly102 and the second tool assembly 104 are structured to form the formedblank truncated protrusion 20 with a thickness that is between about0.0003 inch and 0.002 inch thinner than the formed blank sidewall 14.

Thus, as shown in FIG. 10, a method of forming a formed blank within atooling assembly 100, as described above, includes forming 1000 a blank1 of material to include a base 12 and a depending sidewall 14, clamping1002 the blank 1 between the first tool assembly 102 and the second toolassembly 104 at the periphery of the base 12, and stretching 1004 thebase 12, thereby thinning a portion of the base 12 relative to thesidewall 14 to form a stretched portion 38. In an exemplary embodiment,stretching 1004 the base 12, thereby thinning a portion of the base 12relative to the sidewall 14 to form a stretched portion 38 includesstretching 1006 the base stretched portion so as to have a generallyuniform thickness. Further, stretching 1004 the base 12, therebythinning a portion of the base 12 relative to the sidewall 14 to form astretched portion 38 includes forming 1010 a truncated protrusion 20. Inan exemplary embodiment, forming 1010 a truncated protrusion 20 includesforming 1012 a truncated dome 22.

To form the truncated dome 22 described above, forming 1012 a truncateddome includes: forming 1020 a dome with a first generally curvilinearportion and a second generally curvilinear portion, forming 1022 thefirst generally curvilinear portion about a first center, and forming1024 the second generally curvilinear portion about a second center.Further, to form the truncated dome 22 described above forming 1000 theblank 1 of material to include a base 12 and a depending sidewall 14includes forming 1030 the sidewall 14 with a thickness generallycorresponding to the base gauge of the material. Further, stretching1004 the base 12, thereby thinning a portion of the base 12 relative tothe sidewall 14 includes forming 1032 the stretched portion 38 with athickness that is less than the formed blank sidewall 14. Further, in anexemplary embodiment, stretching 1004 the base 12, thereby thinning aportion of the base 12 relative to the sidewall 14 includes forming 1036the stretched portion 38 with a thickness that is between about 0.0003inch and 0.002 inch thinner than the sidewall 14.

The process described above discloses forming a blank 1 into a cup 2having a truncated protrusion 20. It is understood that such a cup 1 isthen formed into a can body 5 either in the same device or the cup 2 istransported to a bodymaker, as is known. The can body 5 made from such acup 2 also includes the truncated protrusion 20. Alternatively, whenforming the cup 1 into a can body 5, the thinned portion is reformedinto a traditional dome that is generally concave; i.e., the dome 9 doesnot have a generally planar portion. As used herein, a can body 5 madefrom a cup 2 having a truncated protrusion 20 is also a formed blank 10having a truncated protrusion 20 regardless of whether the truncatedprotrusion 20 is reformed at a later stage of processing.

That is, as shown in FIGS. 8A-8E, cup 2 with a truncated protrusion 20is formed into a beverage can body 5′. That is, as shown in FIGS. 8A-8C,the cup 2 is reformed by inverting the truncated protrusion 20. Duringthis forming process, the bottom of the cup 2 is reformed so as to besubstantially planar. Thus, as shown in FIGS. 8D and 8E, when the canbeverage can body 5′ is reformed with a dome, the bottom of the cup 2forms over the domer 180 with no loose metal as in the prior art.

Similarly, FIGS. 9A-9E show the formation of a food can body 5″. In thisprocess, the cup 2 and the truncated protrusion 20 are reformed assubstantially planar elements. Because the generally planar portion 32is already generally planar, the reformed can body does not include anoffset portion which is a remnant of the dome.

While specific embodiments of the invention have been described indetail, it will be appreciated by those skilled in the art that variousmodifications and alternatives to those details could be developed inlight of the overall teachings of the disclosure. Accordingly, theparticular arrangements disclosed are meant to be illustrative only andnot limiting as to the scope of invention which is to be given the fullbreadth of the claims appended and any and all equivalents thereof.

What is claimed is:
 1. A formed blank comprising: a body including abase; and the base including a truncated protrusion.
 2. The formed blankof claim 1 wherein the truncated protrusion is a truncated dome.
 3. Theformed blank of claim 2 wherein: the truncated dome includes a firstgenerally curvilinear portion and a second generally curvilinearportion; the truncated dome first generally curvilinear portion having afirst center; and the truncated dome second generally curvilinearportion having a second center.
 4. The formed blank of claim 3 wherein:the truncated dome first generally curvilinear portion is a firstgenerally arcuate portion; and the truncated dome second generallycurvilinear portion is a second generally arcuate portion.
 5. The formedblank of claim I wherein the stretched portion of the truncatedprotrusion has a generally uniform thickness.
 6. The formed blank ofclaim 1 wherein the formed blank has a base gauge and wherein; the bodyincludes a sidewall depending from the base: the sidewall has athickness generally corresponding to the base gauge; and the truncatedprotrusion has a thickness that is less than the sidewall.
 7. The formedblank of claim 6 wherein the truncated protrusion has a thickness thatis between about 0.0003 inch and 0.002 inch thinner than the sidewall.8. The formed blank of claim 1 wherein the formed blank has a reducedvolume.
 9. Tooling assembly for forming a blank of material into aformed blank, the formed blank including a base and a dependingsidewall, the tooling assembly comprising: a first tool assembly; asecond tool assembly; the first tool assembly and the second toolassembly structured clamp the blank of material at the periphery of thebase; the first tool assembly and the second tool assembly structured tostretch a portion of the base and thereby thin the base stretchedportion relative to the sidewall; and wherein the base stretched portionis generally uniform in thickness.
 10. The tooling assembly of claim 9wherein: the first tool assembly includes a forming punch; the secondtool assembly includes a forming surface; wherein the forming surfaceincludes a truncated protrusion forming profile; and wherein the formingpunch moves the blank of material into contact with the truncatedprotrusion forming profile.
 11. The tooling assembly of claim 10 whereinthe forming surface includes a truncated dome forming profile.
 12. Thetooling assembly of claim 11 wherein: the truncated dome forming profileincludes a first generally curvilinear portion and a second generallycurvilinear portion; the truncated dome forming profile first generallycurvilinear portion having a first center; and the truncated domeforming profile second generally curvilinear portion having a secondcenter.
 13. The tooling assembly of claim 12 wherein: the truncated domeforming profile first generally curvilinear portion is a first generallyarcuate portion; and the truncated dome forming profile second generallycurvilinear portion is a second generally arcuate portion.
 14. Thetooling assembly of claim 9 wherein the blank of material has a basegauge prior to being formed and wherein: the first tool assembly and thesecond tool assembly are structured to form the blank of material into aformed blank including a base and a sidewall; the first tool assemblyand the second tool assembly are structured to form the formed blankbase with a truncated protrusion; and the first tool assembly and thesecond tool assembly are structured to form the formed blank sidewallwith a thickness about the same as the base gauge; and the first toolassembly and the second tool assembly are structured to form the formedblank truncated protrusion with a thickness that is less than the formedblank sidewall.
 15. The tooling assembly of claim 14 wherein the firsttool assembly and the second tool assembly are structured to form theformed blank truncated protrusion with a thickness that is between about0.0003 inch and 0.002 inch thinner than the formed blank sidewall.
 16. Amethod of forming a formed blank within a tooling assembly, the toolingassembly including a first tool assembly and a second tool assembly, themethod comprising: forming a blank of material to include a base and adepending sidewall; clamping the blank between the first tool assemblyand the second tool assembly at the periphery of the base; andstretching the base thereby thinning a portion of the base relative tothe sidewall to form a stretched portion.
 17. The method of claim 16stretching the base thereby thinning a portion of the base relative tothe sidewall to form a stretched portion includes stretching the basestretched portion so as to have a generally uniform thickness.
 18. Themethod of claim 16 wherein stretching and thereby thinning a portion ofthe base relative to the sidewall to form a stretched portion includesforming a truncated protrusion.
 19. The method of claim 18 whereinforming a truncated protrusion includes forming a truncated dome. 20.The method of claim 18 wherein forming a truncated dome includes:forming a dome with a first generally curvilinear portion and a secondgenerally curvilinear portion; forming the first generally curvilinearportion about a first center; and forming the second generallycurvilinear portion about a second center.
 21. The method of claim 16wherein the blank has a base gauge and wherein forming the blank ofmaterial to include a base and a depending sidewall and stretching andthereby thinning a portion of the base relative to the sidewall to forma stretched portion include: forming the sidewall with a thicknessgenerally corresponding to the base gauge; and forming the stretchedportion with a thickness that is less than the formed blank sidewall.22. The method of claim 21 wherein forming the stretched portion with athickness that is less than the formed blank sidewall includes formingthe stretched portion with a thickness that is between about 0.0003 inchand 0.002 inch thinner than the